The present invention relates generally to image displays.
Image displays include emissive displays, such as phosphor displays used in cathode tube-based television and computer monitors, and transmissive displays, such as projection displays used for large screen TVs. An emissive display works by emitting visible light from pixels that are excited by, e.g., electron beams or fluorescent lamps. In the case of conventional electron beam-based displays, the electron beam is scanned across the pixels as appropriate to excite the pixels to produce a demanded image. In the case of fluorescent lamp-based displays such as plasma displays, ultraviolet light from a gas discharge is directed to appropriate pixels that are physically shielded from each other, with the pixel illumination pattern necessary to produce the demanded image not being established by scanning the UV light, which is simply a discharge from the lamp, but by appropriately blocking the UV light to impinge only on the desired pixels. Both of the above-mentioned emissive displays require the presence of a vacuum within the device, which can complicate manufacturing and raise costs.
Because the weight of some emissive displays becomes infeasibly large in the case of large screen displays, e.g., displays having sizes of 40xe2x80x3-60xe2x80x3 or more, the above-mentioned transmissive displays have been provided, an example of which is the projection display. A projection display works by projecting pixellated light from a relatively small source onto a relatively large projector, which xe2x80x9ctransmitsxe2x80x9d the light toward the viewers.
As recognized herein, while effective, large screen projection-type displays suffer from the drawback of relatively low image quality, compared to the image quality afforded by a smaller emissive display. On the other hand, current emissive display technology, as noted above, cannot easily be used to establish large screen displays owing to weight and other practical restrictions. Nevertheless, the present invention recognizes that it would be desirable to provide a large screen emissive display to overcome the image quality drawback of many large transmissive displays.
A method for making a color separator configured for an image display apparatus includes providing a substrate, and establishing phosphor-based red, green, and blue subpixels on the substrate. The subpixels are covered with at least one refraction layer. A color selection mask layer is printed onto the refraction layer to shield the blue and green subpixels from a first beam, shield the red and green subpixels from a second beam, and shield the red and blue subpixels from a third beam.
Preferably, the display is a large screen phosphor display, and the color selection mask is ink-jet printed onto the refraction layer. The color selection mask defines plural excitation light apertures defining variable pitches established based on the locations of the respective excitation light apertures relative to the display.
In another aspect, a method for producing a demanded image includes establishing a mask on a phosphor display. The mask has apertures defining pitches between adjacent apertures. At least one pitch is different from another pitch. The method includes receiving the demanded image, and directing light onto a display through the mask.
The details of the present invention, both as to its structure and operation, can best be understood in reference to the accompanying drawings, in which like reference numerals refer to like parts, and in which: